It has commonly been the practice to separate the caster and the rolling mill in order to enable product, which has been prepared by a variety of preliminary processing procedures, to be preliminarily processed and thereafter introduced to the rolling line. More recently, since the development of "hot charging" processes, it is known to provide transport means and storage devices for handling cut to length billets or blooms and to introduce them while hot to a heating furnace. While this practice saves and reduces the need for billet storage, it suffers the drawbacks of reduced material output due to the need for cropping the cast product into short lengths, the presence of short bars in the bed, and the generation of scale in the furnace.
Although several of these defects have been overcome by the method for the continuous casting of long products as described in European Patent Application No. EP 0 761 327 to Meroni, et al. and assigned to the assignee hereof, the disclosed method suffers from its own drawbacks that an induction furnace is used before the rolling process to increase the billet surface temperature and then enable its equalization in an air section. This concept is no longer applied in the present invention, according to which the furnace is used to guarantee the stay time after the equalization. Furthermore, in the present invention there is the possibility of having a longer heating time and thus a softer heating curve. This reduces the thermal stress on the material and improves both its quality and the temperature homogeneity through the bloom cross section.
It is to the amelioration of these drawbacks that the present invention is directed.